# Wehrli 17-19 L5P Duramax Billet Anodized Transmission Cooler Thermostat Bypass Plug

As a direct replacement for the failure prone OEM thermostat, the Transmission Cooler Thermostat Bypass Plug can drop fluid temperature from 15-50 degrees F by reducing fluid flow restriction to the trans cooler. In the stock application, we've seen the valve fail forcing trans fluid around the cooler in warm weather conditions that cause dangerous fluid temperatures for built and stock transmissions alike. - - Recommended for trucks with stock or built transmissions and performing heavy towing in warm climates to help keep fluid temperatures in check. - - The WCFab Transmission Cooler Thermostat Bypass Plug is a quick and easy install and will work with the following range of GM vehicles equipped with a factory installed transmission cooler thermostat bypass (6L80, 6L90, 8L90): - - 2017-2019 Chevrolet Silverado & GMC Sierra 2500HD/3500HD with 6.6L Duramax Diesel - 2014-2018 Chevrolet Silverado & GMC Sierra 1500 with 4.3L 6 Cyl, 5.3L 8 Cyl, and 6.2L 8 Cyl Gas Engines - 2015-2020 Chevrolet Suburban, Tahoe & GMC Yukon with 5.3L 8 Cyl, and 6.2L 8 Cyl Gas Engines - 2015 Cadillac Escalade with 6.2L 8 Cyl Gas Engine

-   Experience fluid temperature drops from 15-50 degrees F
-   Direct replacement of the failure prone OEM thermostat
-   CNC Machined Billet Aluminum Thermostatic Bypass Plug
-   Easy swap back to OEM setup for cold weather use
-   Reduces fluid flow restriction to trans cooler
-   High temperature silicone O-ring seals
-   Black Anodized Finish
-   Simple Installation

This Part Fits:

Year

Make

Model

Submodel

2015

Cadillac

Escalade

Base

2015

Cadillac

Escalade

Luxury

2015

Cadillac

Escalade

Platinum

2015

Cadillac

Escalade

Premium

2016-2018

Chevrolet

Silverado 1500

Custom

2014-2018

Chevrolet

Silverado 1500

High Country

2015-2018

Chevrolet

Silverado 1500

LS

2014-2018

Chevrolet

Silverado 1500

LT

2014-2018

Chevrolet

Silverado 1500

LTZ

2015-2018

Chevrolet

Silverado 1500

SSV

2014-2018

Chevrolet

Silverado 1500

WT

2017-2019

Chevrolet

Silverado 2500 HD

High Country

2017-2019

Chevrolet

Silverado 2500 HD

LT

2017-2019

Chevrolet

Silverado 2500 HD

LTZ

2017-2019

Chevrolet

Silverado 2500 HD

WT

2017-2019

Chevrolet

Silverado 3500 HD

High Country

2017-2019

Chevrolet

Silverado 3500 HD

LT

2017-2019

Chevrolet

Silverado 3500 HD

LTZ

2017-2019

Chevrolet

Silverado 3500 HD

WT

2015-2020

Chevrolet

Suburban

LS

2015-2020

Chevrolet

Suburban

LT

2015-2016

Chevrolet

Suburban

LTZ

2017-2020

Chevrolet

Suburban

Premier

2015-2020

Chevrolet

Tahoe

LS

2015-2020

Chevrolet

Tahoe

LT

2015-2016

Chevrolet

Tahoe

LTZ

2015-2020

Chevrolet

Tahoe

PPV

2017-2020

Chevrolet

Tahoe

Premier

2015-2020

Chevrolet

Tahoe

SSV

2014-2018

GMC

Sierra 1500

Base

2014-2018

GMC

Sierra 1500

Denali

2014-2018

GMC

Sierra 1500

SLE

2014-2018

GMC

Sierra 1500

SLT

2017-2019

GMC

Sierra 2500 HD

Base

2017-2019

GMC

Sierra 2500 HD

Denali

2017-2019

GMC

Sierra 2500 HD

SLE

2017-2019

GMC

Sierra 2500 HD

SLT

2017-2019

GMC

Sierra 3500 HD

Base

2017-2019

GMC

Sierra 3500 HD

Denali

2017-2019

GMC

Sierra 3500 HD

SLE

2017-2019

GMC

Sierra 3500 HD

SLT

2015-2020

GMC

Yukon

Denali

2015-2020

GMC

Yukon

SLE

2015-2020

GMC

Yukon

SLT

2015-2020

GMC

Yukon XL

Denali

2015-2020

GMC

Yukon XL

SLE

2015-2020

GMC

Yukon XL

SLT

## Details

- **Price:** 106.64 CAD
- **Vendor:** Wehrli
- **Type:** Thermostat Housings

## Variants

| Variant | Price | Available |
|---------|-------|-----------|
| Default Title | 106.64 CAD | In stock |

## Images

- Photo - Primary
- User 1
- User 3
- User 1
- User 1
- User 2
- User 1
- Logo Image

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> Source: [Standard Auto Part](https://www.standardautopart.com/products/wehrli-17-19-l5p-duramax-billet-anodized-transmission-cooler-thermostat-bypass-plug)
> Updated: 2026-07-03